Improvement in hollow augers



UNITED STATES PATENT OFFICE.

GEORGE N. STEARNS, OFSYRACUSE, NEW YORK.

IMPROVEMENT IN i HOLLOW AUGERS.

Specification forming part of Letters Patent No. 39.841, dated September 8, 1863; autedated January 16, 1863.

To all whom it may concern:

Be it known that I, GEoRGE N. S'rEARNs, of Syracuse, county of Onondaga, State of New York,have invented certain new and useful Improvements in Hollow Angers; and I do hereby declare and ascertain the same, reference being had to the accompanying drawings, in whicl Figure l is a perspective view of my improv ments combined inthe form of an adjustabl ho low auger. Fig. 2 is a view of one of the adjustable thimbles detached. Fig 3 is a dt ched view of the knife or cutter. Fig.4 is a detached view ofthe adjustable shank.

Like letters refer to like parts in all the drawings.

I am aware thatl several attempts have been madt t l construct an a ljustable hollow auger,

but e\ ery such device that l have seen was either too expensive or too complicated or too inconvenient in practical use. l have found in my experience that there are three different ways in which this tool should be adjustable-viz., first, by means of thimbles, like O in Fig.` 1, (held in place by setscrews L,) with diiierentsized internal apertures for different-sized tenons; second, by means of a movable knife or cutter, B, not only to conform to ditlerent-sized thimbles, but also so attached as to admit of a quick aid convenient minute adjustment to the slightvariatio sin the diameter ot' different bits made and intended for the same size,but which frequently differ perceptibly in the actual diameter of the hole which they bore; and a third, in the length of tenon which the auger will cut, which can be regulated by the adjustable shank A, which is set to any number of inches desired in the length ofthe tenon and held firmly in place by an ordinaryT set-screw, (marked M in Fig. 1.) 1n order to set the cutter B as rmly as heavy work requires and preserve sufficient strength in the body of the anger marked l), I und it necessary to cast this part ct' my device of strong niaterial, like iron or brass, and with a mortise in which the said cutter is screwed by setscrews P, O, and N, Fig. 1, and in order to attain readily the minute adjustment of the cutter necessary to ada-ptthe size ofthe tenon to the slight variations of bitsintended to be ofthe same size, but which often vary slightly, l find a peculiar arrangement of the set-screw necessarythe set-screws P and O beingl near the outer end of the cutter and so as to act as a center ot motion upon Which the inner end of the cutter may be moved and ad justed in the most convenient and accurate manner by the set-screw N. Thisform ofthe body of the auger imparts great strength and ligh ness, and this arrangement of the setscrews therein secures the cutter firmly for the heaviest kind of work, and admits ofa minute adjustment of the point of the cutter to the slightest variation in the size ofthe bit. I make the tnortise through the body of the auger considerably wider than the thickness ofthe cutter, in order to permit a sidewise adjustmtnt of the cutter to vary the thickness of chip or rapidity of cut, and l adjust this by means ofthe set-screws P and O, and by them hold the cutter in any position desired for this purpose. The set-screw N is also convenient for adjusting the point of the cutter to compensate for its wear in use, and to vary its point laterally for the minute adjustment above described, and for this purpose, and also to obtain a drawing cut, 1 locate my cutter so that its edge will stand at an angle of about fortyve degrees from a line extending from its point to the center of the thimble. By this` means a drawing cutis obtained and also a very convenient lateral adjustment ot' the point ot' the cutter.

Having thus fully described my invention, WhatI claim therein as new, and desire to secure by Letters Patent, is-

l. The construction ot' the body of the auger, substantially as described, and combining therewith the adjustable thimble O, the adjustable cutter B, and the adjustable shank A, for the. purposes substantially as specified.

2. Ooniining the cut-ter Within the mortise and sustaining and locating it so as to obtain the longitudinal, vertical, and lateral adjustment, and thel drawing cut, substantially as and for the purposes described.

GEO. N. STEARNS.

Witnesses:

WILLIAM WALLACE, ANDREW J. SMITH. 

